Such catheter sets are used for a variety of purposes in a variety of fields of medicine but not for continuous plexus anathesia.
Since 1946, methods of continuous plexus anathesia with different modes of access to the plexus brachialis have been described. Heretofore to achieve this conductive anathesia only such adjuvants have been used as vein retention canulas, epideral catheters with Tuohy-needles, spinal needles with teflon catheters drawn over them, or also vein-puncturing canulas combined with vein retension catheters. An objection of all these methods is the danger of damaging the nerves and/or blood vessels through the sharp canula tip. Even the Tuohy-needle is not complete safe in these respects.
In order to avoid this danger of nerve and/or blood vessel damage through the sharp canula tip, an immobile needle of Zenz and Glocker has been developed for plexus anathesia (German Gebrauchsmuster No. 6810657.7). This needle makes possible the one time injection of a local anesthetic. When the effect of this has worn off, a new puncture must be made. The operation level reaches a maximum, the decline of which depends of the pharmacological properties of the local anesthetic to be used. By reason of its conception, this needle is suitable predominantly for analgesia or anesthesia of a maximum of six to ten hours and is hence used predominantly in the operative field. The shortness of the needle presents a relatively steep angle to the neurovascular axillary fasciae with the danger especially for beginners, of nerve lesion and possibly also blood vessel damage. The thin needle perforates neurovascular fasciae of the axilla with a light "click" phenomenon and a slightly evident decrease in resistance to a constantly exerted pressure through an attached syringe filled with a physiological NaCl-solution. With this needle, a catheter cannot be introduced into the nervovascular membrane.